Detectives are continuing to appeal for witnesses and information following the murder of Mohamed Kakay in Camberwell.
The investigation is now being led by Detective Chief Inspector Cliff Lyons from the Homicide and Major Crime Command.
DCI Lyons said: "We are continuing to appeal for witnesses and anyone with any information to contact us.
"It is believed Mohamed's attacker was around the area of Wilson Road, Camberwell Grove and Camberwell Church Street and the roads leading off from those main routes between 9am and 9.30am on Saturday, November 19th.
"I am particularly appealing to anyone who was in the area between these times that may have been recording video footage from bike helmets, or dashboard cameras or mobile phones. Anyone providing this would be greatly assisting the investigation team."
Any witnesses or anyone with any information are urged to call the incident room on 020 8721 4961.
To give information anonymously call Crimestoppers on 0800 555 111 or visit crimestoppers-uk.org
A 36-year-old man who had previously been arrested and bailed in connection the investigation has now been eliminated from enquiries.
On Saturday, 19 November, police were called by the London Ambulance Service (LAS) at approximately 09:15hrs to reports of a stabbing outside St Giles' Church in Camberwell Church Street, SE5.
Officers attended and found a man - later identified as Mohamed Kakay, 33, from Bromley - suffering from stab injuries. He was taken by LAS to a south London hospital but he died later that afternoon. Next of kin were informed.
A post-mortem examination took place on Sunday, 20 November and found the cause of death to be a single stab wound to the abdomen.
At this early stage of the investigation it is believed that Mohamed had entered the grounds at the rear of St Giles' Church at around 09:00hrs.
He was stabbed but managed to stagger along the path at the side of the church to the front and out onto Camberwell Church Street, collapsing near Wilson Road.
Some members of the public stopped and administered first aid until emergency services arrived.